Odd-indexed terms of A124297.

Terms

a(0) =11a(1) =31a(2) =151a(3) =911a(4) =5951a(5) =40051a(6) =272611a(7) =1863551a(8) =12760031a(9) =87424711a(10) =599129311a(11) =4106261531a(12) =28144128251a(13) =192901135711